In-line roller skates have seen great popularity. This popularity is due in part to constant improvements to decrease the effort to propel oneself and make the sport more enjoyable.
Known bearing assemblies include a pair of axially spaced ball bearings concentrically mounted within an annular wheel hub and mounted on a generally cylindrical annular bearing spacer or axle sheath. Each ball bearing typically includes a plurality of bearing balls mounted between inner and outer bearing races. Known bearing spacers conventionally comprise an enlarged center portion and reduced end portions. The inner races of the two ball bearings are commonly mounted on the respective reduced end portions in abutment with the respective opposite radial shoulders of the enlarged center portion so that the two ball bearings are axially spaced from each other.
Wheel bearing quality and condition significantly affect the amount of effort required to propel oneself on a pair of in-line skates. However, even high quality bearings that are in top condition will degrade in performance as friction between the bearing balls and the bearing races causes heat to build up within those structures. Heat build-up in the wheel bearings and bearing races of a typical ball bearing assembly causes those parts to expand in size and increases rolling friction. Increased rolling friction requires that a skater exert greater effort to maintain a given speed.
What are needed are improvements to wheel bearing assembly design that reduce rolling friction by reducing heat build-up.